Electronic fetal monitoring (EFM) is used during labor to monitor the fetal heart rate and detect any changes that could indicate impaired oxygenation. It analyzes the fetal heart rate baseline, variability, and any accelerations or decelerations in response to contractions. While EFM provides useful data, it has limitations as it does not reliably identify compromised fetuses and can increase rates of operative intervention. When abnormalities are detected, interventions like turning the patient, administering oxygen, or stopping oxytocin infusion may be performed to attempt to improve the fetal heart rate tracing through intrauterine resuscitation.
3. • The primary objective of EFM is to provide information
about fetal oxygenation and prevent fetal injury that
could result from impaired fetal oxygenation during
labor.
• This is achieved by detecting fetal heart rate changes
early before they are prolonged and profound.
EFM
4. • Adequate fetal oxygenation requires five related factors:
• Adequate maternal blood flow and volume to the
placenta.
• Adequate oxygen saturation in maternal blood.
• Adequate exchange of oxygen and carbon dioxide in the
placenta.
• An open circulatory path between the placenta and the
fetus through vessels in the umbilical cord.
• Adequate fetal circulatory and oxygen-carrying
functions.
Fetal Oxygenation
5. • Review: Oxygen rich and nutrient rich blood from the
mother enters the intervillous spaces of the placenta
through the spiral arteries.
• Oxygen and nutrients in the maternal blood pass into the
fetal blood that circulates in capillaries in the intervillous
spaces.
• CO2 and other waste products pass from the fetal blood
into the maternal blood at the same time.
• Maternal blood carrying fetal waste products drains from
the intervillous spaces through endometrial veins and
returns to the mother’s circulation for elimination.
Uteroplacental
Exchange
6. • Substances pass back and forth between mother and fetus
without mixing of maternal and fetal blood if fetal
capillaries remain intact.
• During labor contractions gradually compress the spiral
arteries, temporarily stopping maternal blood flow into
the intervillous spaces.
• Thus during contractions the fetus depends on the oxygen
supply already present in body cells, along with
intervillous spaces. Oxygen supply in these areas is
enough for about 1 to2 minutes.
Exchange continued:
7. • The average heart rate measured over a 2 minute period
within a 10 minute window
• Normal=110-160
• Brady=<110 for 10 minutes
• Tachy=>160 for 10 minutes
• Pre-term may have >160 due to immature
parasympathetic NS
Baseline FHR
8. • Most important component of the FHR
• Irregular fluctuations in the baseline fetal heart rate.
• Measured as the amplitude of the peak to trough in bpm
• Evaluates fetal autonomic nervous system, adequate 02
status promotes normal FX
• Long-term variability(LTV) broader fluctuations of the
FHR
• Short-term variability(STV) beat-to-beat variability, only
with IFSE
• No variability=fetal compromise
Variability
13. • Accelerations (accels) – transitory abrupt increases in the
FHR above the baseline,15 bpm above baseline FHR
greater than 15 sec less than 2 minutes. Reassuring; thus
denoting fetal movement and fetal well-being and are the
basis for nonstress testing.
• Decelerations- transient fall in FHR caused by
stimulation of the parasympathetic NS.
• Early=head compression
• Late=utero-placental insufficiency
• Variable=cord compression
Periodic changes
15. • Deceleration with each contraction
• Mirror image when contraction begins
the heart rate begins to drop
• Action – prepare for birth
Head compression
17. • Deceleration with each contraction
• Late onset, usually see a decrease in variability
• Action=intra-uterine resuscitation
• If on Pitocin – turn it OFF
• Increase mainline fluid volume, bolus with LR
• O2 via face mask at 8-10 L
• Turn to left side, or whatever position best for blood flow
• Scalp stimulation?
Late decelerations
19. • Occurs randomly
• Not a problem if occasional and returns to baseline
• If frequent, long return, < variability=intrauterine
resuscitation.
• Turn to left side
• Pitocin off and increase fluids
• O2 via face mask at 8- 10 L
• Amnioinfusion – warm NS – only with variables!!!!
Variable deceleration
20. • 1.If Pitocin is on turn it off!
• 2. Turn the patient
• 3. IV bolus
• 4. Oxygen administration. 10 Liters per face mask. Non
rebreather.
Intrauterine
Resusutation
21. Prolapsed cord
• Do not remove fingers
after exam
• Relieve pressure from
presenting part
• Call for help, prepare for
emergency C/S
• Remain calm
22.
23. • Reduced mobility
• May require frequent adjustment of equipment to obtain
continuous tracing
• Best identifies the well oxygenated fetus…does not
reliably identify the compromised fetus
• Increased operative intervention
EFM
Limitations
24. • Intra-uterine resuscitation
• Measures create anxiety, fear, and loss of control
• Remain calm, educate patient and family, and choose
words wisely
• Report all interventions to MD
Interventions
25. • Supplies more data, becomes part of the permanent
record
• Shows FHR in relation to stimuli
• Provides a feeling of safety for the parent
• Allows nurse/patient ratio to be 1:2 with central
monitoring
EFM
Advantages